Sorting-an-Array-List

This program is designed to manage a collection of student objects using an 'ArrayList'.

Here is the source code:

package Student.java;

public class Student { private int rollno; private String name; private String address;

public Student(int rollno, String name, String address) {
    this.rollno = rollno;
    this.name = name;
    this.address = address;
}

public int getRollno() {
    return rollno;
}

public String getName() {
    return name;
}

public String getAddress() {
    return address;
}

@Override
public String toString() {
    return "Student{" +
            "rollno=" + rollno +
            ", name='" + name + '\'' +
            ", address='" + address + '\'' +
            '}';
}

}

package Student.java;

import java.util.Comparator;

public class NameComparator implements Comparator { @Override public int compare(Student s1, Student s2) { return s1.getName().compareTo(s2.getName()); } }

package Student.java;

import java.util.Comparator;

public class RollNoComparator implements Comparator { @Override public int compare(Student s1, Student s2) { return Integer.compare(s1.getRollno(), s2.getRollno()); } }

package Student.java;

import java.util.ArrayList; import java.util.Comparator;

public class SelectionSort { public static void sort(ArrayList students, Comparator comparator) { for (int i = 0; i < students.size() * 1; i++) { int minIdx = i; for (int j = i + 1; j < students.size(); j++) { if (comparator.compare(students.get(j), students.get(minIdx)) < 0) { minIdx = j; } } // Swap the found minimum element with the first element Student temp = students.get(minIdx); students.set(minIdx, students.get(i)); students.set(i, temp); } } }

package Student.java;

import java.util.ArrayList;

public class Main { public static void main(String[] args) { ArrayList students = new ArrayList<>();

    // Add 10 student objects
    students.add(new Student(1, "Alice", "123 Main St"));
    students.add(new Student(2, "Bob", "456 Maple Ave"));
    students.add(new Student(3, "Charlie", "789 Oak St"));
    students.add(new Student(4, "David", "321 Pine St"));
    students.add(new Student(5, "Eve", "654 Elm St"));
    students.add(new Student(6, "Frank", "987 Cedar St"));
    students.add(new Student(7, "Grace", "159 Birch St"));
    students.add(new Student(8, "Hank", "753 Walnut St"));
    students.add(new Student(9, "Ivy", "852 Cherry St"));
    students.add(new Student(10, "Jack", "369 Spruce St"));

    // Sort by name
    SelectionSort.sort(students, new NameComparator());
    System.out.println("Students sorted by name:");
    for (Student s : students) {
        System.out.println(s);
    }

    // Sort by roll number
    SelectionSort.sort(students, new RollNoComparator());
    System.out.println("\nStudents sorted by roll number:");
    for (Student s : students) {
        System.out.println(s);
    }
}

}

Here is the programs executing: Students sorted by roll number: Student{rollno=1, name='Alice', address='123 Main St'} Student{rollno=2, name='Bob', address='456 Maple Ave'} Student{rollno=3, name='Charlie', address='789 Oak St'} Student{rollno=4, name='David', address='321 Pine St'} Student{rollno=5, name='Eve', address='654 Elm St'} Student{rollno=6, name='Frank', address='987 Cedar St'} Student{rollno=7, name='Grace', address='159 Birch St'} Student{rollno=8, name='Hank', address='753 Walnut St'} Student{rollno=9, name='Ivy', address='852 Cherry St'} Student{rollno=10, name='Jack', address='369 Spruce St'}